So I just had the time measurement according to the past two swings. All the following time is by UTC.
Firstly, it might reach the top, which is 23k, at around 7/20 16:00 - 7/21 4:00. And then it goes sharply, it might reach a low, which may be just like 17.6k - 19k, at around 7/25 8:00 - 7/25 12:00.